1. Field of the Invention
The present invention relates to a solder dispenser for supplying a solder member to a predetermined place.
2. Description of the Prior Art
Up to now, various mechanisms have been used as a mechanism which is an example of a solder dispenser, conveys a solder member, and is incorporated in a soldering apparatus. For example, a soldering apparatus equipped with a solder supply portion which rotates a multi-hole disk to supply a solder ball into a soldering apparatus intermittently is known. A conventional example of a soldering apparatus equipped with a solder supply portion using a multi-hole disk will be explained below with referring to drawings.
FIG. 4 is a partial sectional view of the soldering apparatus equipped with a conventional solder supply portion. A conventional soldering apparatus 500 is equipped with a nozzle assembly 501, a solder supply portion for supplying a solder ball 507 to the nozzle assembly 501, laser equipment 517 for giving heat rays to a solder ball, and a gas supply portion 535 which supplies a compressed gas in order to inject the solder ball 507 which is melted.
The solder supply portion is equipped with a multi-hole disk 533 which receives the solder ball 507 from a storage portion, which stores the solder balls 507 but is not shown, and conveys it, and a driving portion which rotates the multi-hole disk 533, not shown, intermittently but is not shown.
Holding holes 537 are bored at equal intervals in an outer periphery side of the multi-hole disk 533, and one of the solder balls 507 is held in each of the holding holes 537. The multi-hole disk 533 holding the solder balls 507 is rotated, and conveys one of the solder balls 507 from a storage portion on an opening end portion of a solder introducing passage 521 which will be mentioned later. The solder ball 507 which reaches on the opening end portion advances into the solder introducing passage 521.
The nozzle assembly 501 is constituted by a nozzle 503 for injecting a solder ball 507, and a nozzle body 505 for supporting the nozzle 503.
The nozzle body 505 is equipped with a laser introducing passage 519 extended in a vertical direction, and the solder introducing passage 521 whose one end portion is connected to the laser introducing passage 519 and which is extended in a direction of inclining against the vertical direction. Another end portion of the solder introducing passage 521 opens near the multi-hole disk 533. In addition, the laser introducing passage 519 communicates with a containing portion 509 of the nozzle 503 mentioned later.
A tapered-off cylindrical nozzle 503 is equipped with the containing portion 509, an opening in a top side of the containing portion 509 communicates with the laser introducing passage 519 of the nozzle, and a lower opening is an opening portion 511 for injecting a solder. An internal diameter of the nozzle 503 is sized to be larger than an outer diameter of the solder ball 507 so that the solder ball 507 can roll, and is sized to be smaller than the outer diameter of the solder ball 507 near the opening portion 511. Therefore, the solder ball 507 which advances into the solder introducing passage 521 passes through the laser introducing passage 519 and containing portion 509 and is held by the opening portion 511 in the nozzle 503.
The solder ball 507 which is located in the opening portion 511 is melted by radiation of laser light from the laser equipment 517 to be injected to the external of the nozzle 503 by the compressed gas supplied through a gas inlet 541 and the solder introducing passage 521 from the gas supply portion 535 (Refer to Japanese Patent Application Laid-Open No. 11-534409 (FIG. 1)).
It becomes difficult that the multi-hole disk 533 of the conventional soldering apparatus 500 mentioned above holds solder balls securely in the holding holes 537 in connection with miniaturization of a diameter of a solder ball. In addition, since a solder ball is a soft material, there is a possibility that the solder ball may deform and chippings of the solder ball may be generated, by friction arisen in the solder ball when the multi-hole disk 533 rotates. As a result, there is a possibility that a solder ball may clog a holding hole 537 of the multi-hole disk 533. Since the multi-hole disk 533 rotates with a solder ball remaining in a holding hole 537 when the solder ball is clogged in the holding hole 537, there is a possibility of biting.
In addition, in the construction of supplying a compressed gas and injecting a solder ball 507, setting the compressed gas at a predetermined pressure value is an important factor which influences success or failure of an injection. Therefore, it is desirable to make a gas supply route, where a compressed gas reaches a solder ball, a closed space. Here, in the conventional example in FIG. 4, the gas supply route is constituted by the gas inlet 541 of a disk supporting section 539, a holding hole 537 of the multi-hole disk 533, the solder introducing passage 521, the laser introducing passage 519, and the containing portion 509.
Nevertheless, it is necessary to provide predetermined clearance also between a holding hole 537 and a solder ball 507, and, since the multi-hole disk 533 is a rotating member, it is necessary to provide a predetermined clearance 542 between the multi-hole disk 533 and disk supporting section 539 which supports the multi-hole disk 533. Hence, as for a gas supply route, originally, it is desirable for the gas inlet 541, holding hole 537, and solder introducing passage 521 to communicate without a gap. However, it is difficult by the clearance, which exists between the above-mentioned holding hole 537 and solder ball 507, and the clearance 542 of the multi-hole disk 533 which exists in the middle of the gas supply route to make the gas supply route into the closed space. Hence, gas supply pressure becomes unstable as a result.
For example, when a pressure value of a compressed gas becomes smaller than a predetermined value, there is a possibility of a solder member clogging a nozzle by viscosity of a melted solder member. On the contrary, although it is possible to eliminate influence of the viscosity when the compressed gas pressure is larger than a predetermined value, there is a possibility that the solder member which is melted scatters in the air, spreads on a surface of an object of soldering, or rebounds.
In addition, there is a limit of lessening size of the multi-hole disk, which conveys a solder member from a solder storage portion, because of necessity of holding a plurality of solder members, and it is difficult to make its construction further simpler.